The software scare of the millennium sent people in developed nations scrambling to stock up on water, rations and whatever else one might need after the end of the world as we know it. The Y2K bug was expected to cripple computers at midnight on January 1, 2000 because internal clocks did not have the year 2000 programmed in. Systems would revert to an earlier year, such as 1900, computers would fail, and some people feared that planes would fall out of the sky.
The world didn't end after all, but $296.7 billion was spent worldwide from 1995 to 2001 to mitigate the damage, with outages costing $21 billion, according to research firm IDC. U.S. businesses and public agencies spent about $100 billion alone in preparation for Y2K, according to the Commerce Department.